The present invention relates generally to the field of suspension systems. More particularly, the present invention relates to the field of joints or bearings for use in suspension systems.
Spherical-type bearings or joints are commonly used in suspension systems to couple a shock or strut to a control arm in a manner that allows the shock or strut to pivot or rotate around one or more axes relative to the control arm. In order to function properly over a sufficient period of time, spherical bearings are generally lubricated and efforts are made to minimize the amount of debris that enters the bearing, particularly the surfaces that rub against one another as the bearing operates. In order to maintain the lubricated state of the bearing and minimize the amount of debris that enters the bearing, various attempts have been made to seal the bearing.
Some attempts to seal the bearing have involved seating a relatively small lip seal in the outer race of the bearing so that the seal rides on the ball or inner race as the bearing operates. However, in order to seat within the outer race, the lip seal must be relatively small, which tends to reduce the effectiveness of the seal. Moreover, such a seal has a tendency to fall off the edge of the ball or inner race and get crushed by the pin of the bearing when it moves into a maximum rotational position.
Other attempts have been made to seal the bearing by providing a type of flexible covering or boot over the entire bearing. Although such a covering may reduce the amount of debris that enters the bearing, it generally does not provide an effective means of retaining the lubrication within the internal structures of the bearing. Moreover, such a covering may not be appropriate for certain applications and may make visual inspections, repair, and routine maintenance of the bearing more difficult. In addition, in order to properly seal the bearing, such coverings or boots are often assembled tightly around one or more parts of the bearing and/or the components coupled to the bearing. If the different components to which the boot is coupled move relative to one another, particularly if they rotate relative to one another, the tight fit of the boot against each component causes different portions of the boot to move relative to one another, which may cause the boot to twist or wrap up and become damaged.